1. Field of the Invention
The present invention relates generally to valve actuating mechanisms for engines and, more particularly, to a retention device for a valve actuating mechanism for an engine.
2. Description of the Related Art
It is known to provide valve actuating mechanisms to open and close valves of an engine such as an internal combustion engine. These valve actuating mechanisms may be of a finger follower type including a finger follower having a pallet or web engaging a stem of the valve and a dome socket engaging a rounded end of a hydraulic lash adjuster supported by a cylinder head of the engine. The dome socket is known to have a dome with a concave recess or socket therein. Typically, a circular opening or orifice is provided in the dome for spraying lubrication fluid from the dome socket into a camshaft compartment for lubricating a cam and cam follower and associated components of the valve actuating mechanism.
It is known to provide a device for securing the finger follower and hydraulic lash adjuster together. For example, U.S. Pat. No. 5,775,280 to Schmidt et al. discloses a securing device for an actuating lever in a valve control mechanism of an internal combustion engine. In this patent, a hydraulic lash adjuster disposed below a spherical end of a finger follower or lever and has an undercut for receiving a connecting element in the form of a sheet metal retention clip so that the finger follower and the hydraulic lash adjuster form a structural unit. The sheet metal retention clip has a thickness which is smaller than the width of the undercut, so that the connecting element does not spring open during pivoting movements of the finger follower but bears firmly against the socket-like portion of the finger follower and thus does not cause an additional increase of friction in the valve drive mechanism. The sheet metal retention clip exhibits a generally U-shaped configuration and is comprised of an arm, which engages a top surface of the finger follower, and a second, bifurcated arm which is received in the undercut. An intermediate portion connects the arms to each other, with the arms additionally formed with retaining lugs for securing the clip in place.
The above-described patented sheet metal retention clip suffers from the disadvantage that this clip always effects a relative movement in relation to the finger follower or the lash adjuster. Another disadvantage is that the constant relative movement occurring between the retention clip and the finger follower and between the retention clip and the lash adjuster subjects the valve actuating mechanism to additional friction, which is undesired. A further disadvantage of the retention clip is that it does not bear firmly against the finger follower in all operating positions of the valve actuating mechanism as a result of the pivoting motion of the finger follower.
Therefore, it is desirable to provide a retention device to secure the actuating lever or finger follower and the support member or lash adjuster of a valve actuating mechanism to one another, without increasing a friction in the valve drive. It is also desirable a retention device to provide to effect a free movement of the retention device in all pivoted positions of the finger follower. Thus, there is a need in the art to provide a retention device for a valve actuating mechanism that meets at least one of these desires.